Day 8 of 815 minutes

Day 8: Financing Nature — Natural Capital and the UK's Emerging Ecosystem Markets

Natural capital, biodiversity net gain, and the UK's emerging markets for ecosystem services

Walk along almost any river in England this spring and you are looking at an asset that is failing to pay its way. The water regulates flooding, filters pollutants, supports fisheries, and carries nutrients to the sea — services that, if priced, would be worth billions of pounds a year. But none of that value shows up on a balance sheet. When a developer builds houses upstream, or a farmer applies fertiliser that runs into the catchment, the cost of the damage is borne by someone else: downstream residents, water bill payers, the wildlife that depends on the river. Economists call this a failure of the market. Biologists call it the quiet collapse of the systems that keep the economy functioning.

The previous seven days of this course focused on decarbonising the energy system — the carbon side of the environmental ledger. Today we turn to the other side: nature itself. Over the past three years, the UK has begun assembling a financial architecture for natural capital — the stocks of soil, water, woodland, peatland, and biodiversity that underpin everything from agricultural output to urban resilience. The machinery is newer, messier, and more contested than the carbon equivalent, but the direction of travel is clear: nature is being priced, traded, and disclosed in ways that would have seemed inconceivable a decade ago.

The Daily Brief (5 mins)

Why This Matters Right Now

In March 2026, the British Standards Institution published two new standards — BSI Flex 702 (Biodiversity markets) and BSI Flex 704 (Nutrient markets) — alongside a public consultation on Flex 705 (Communities Code of Practice). Together with the 2024 overarching principles standard (Flex 701), these form what the Department for Environment, Food and Rural Affairs has described as the most comprehensive suite of nature market standards anywhere in the world. The publication was accompanied by a government valuation of the UK's natural environment at over £1.5 trillion, delivering more than £36 billion in economic benefits each year.

The timing is not accidental. Three months earlier, on 18 December 2025, the Planning and Infrastructure Act 2025 received Royal Assent, creating a new statutory body of work — Environmental Delivery Plans (EDPs) — and a new state-operated financing vehicle, the Nature Restoration Fund (NRF). Natural England notified the Secretary of State of its intention to prepare 16 EDPs for nutrient catchments and seven for great crested newts within 24 hours of the Act passing. On 10 February 2026, HM Treasury republished its Enabling a Natural Capital Approach guidance — the supplementary companion to the Green Book — with expanded sections on valuing biodiversity and generating new income streams from natural capital.

Taken together, these three developments — the BSI standards, the Planning and Infrastructure Act, and the updated Green Book guidance — mark the moment at which UK natural capital stopped being a concept largely confined to academic papers and became a priced, regulated, and reportable asset class.

The central question for Day 8 is: how does a country learn to finance something it has never put a price on?

The Deep Dive (7 mins)

1. From Dasgupta to Accounting: What "Natural Capital" Now Means in UK Policy

The intellectual foundation for UK natural capital policy is the Dasgupta Review (2021), commissioned by HM Treasury and authored by the economist Sir Partha Dasgupta. Its central argument — that the economy is embedded within nature, not separate from it — has since been absorbed into Treasury guidance, Defra strategy, and financial regulation. The concept splits nature into two parts: stocks (ecosystems and natural resources such as woodlands, peatlands, soils, wetlands, and rivers) and flows (the ecosystem services those stocks deliver, such as pollination, flood attenuation, carbon sequestration, water purification, and biodiversity). The framework is deliberately analogous to financial capital and its returns.

Where this becomes consequential for capital markets is in the mechanisms by which those flows are now being measured, valued, and paid for. The UK has three broad categories of nature market, operating in parallel: compliance markets (where regulation creates mandatory demand), voluntary markets (where corporate buyers pay for verified environmental outcomes), and public payments (where government pays land managers directly, most notably through the Sustainable Farming Incentive). Day 8 focuses on the first two, because those are where private capital is being mobilised at scale.

The sums involved are still modest relative to the energy transition covered earlier in this course. Government analysis estimates the biodiversity units market alone at between £135 million and £274 million per year once fully bedded in. Cumulative carbon sequestration through the Woodland Carbon Code has reached approximately 8 million tonnes of CO₂ equivalent since 2017, and the Peatland Code roughly 750,000 tonnes since 2015. These are small numbers beside the £26 billion-per-year gap identified by the CCC in Day 1. But the institutional scaffolding being assembled is designed to grow these markets by orders of magnitude over the coming decade.

2. The Compliance Markets: BNG, Nutrient Neutrality, and the New Nature Restoration Fund

Biodiversity Net Gain (BNG) became mandatory for major developments in England on 12 February 2024 under the Environment Act 2021. The requirement is straightforward in principle: every in-scope planning application must demonstrate at least a 10% uplift in biodiversity value, measured using Defra's statutory biodiversity metric (version 4.1), and maintained for a minimum of 30 years. Developers must follow the biodiversity gain hierarchy: achieve gains on-site first; if not possible, buy off-site units from private habitat banks; and only as a last resort, purchase statutory biodiversity credits from the government, which are deliberately priced at between £15,000 and over £100,000 per unit to ensure they function as a fallback rather than a primary route to market.

Two significant expansions are now in train. On 16 December 2025, the Housing Secretary announced an area-based exemption for sites under 0.2 hectares — removing small developments from scope to reduce administrative friction — alongside forthcoming consultation on a brownfield exemption. From May 2026, BNG will extend to Nationally Significant Infrastructure Projects (NSIPs), bringing major transport, energy, and water schemes into the market. The Environment Bank, the largest private habitat bank operator, is supporting over 6,000 acres of habitat creation; specialist asset manager Gresham House launched a dedicated biodiversity strategy in 2024 targeting an initial raise of approximately £380 million.

Running in parallel is nutrient neutrality, which applies to 74 local planning authorities in catchments where protected habitats are already in unfavourable condition from excess nitrogen and phosphorus. Unlike BNG, nutrient neutrality has no statutory credit backstop — developers must either mitigate on-site, purchase private offsets from operators such as Wild Capital, or, historically, see their developments stall entirely. The Environmental Audit Committee estimated in 2023 that 100,000 homes were being held up by these requirements.

This is the problem that the Planning and Infrastructure Act 2025 is designed to solve. Part 3 of the Act introduces Environmental Delivery Plans — area-based conservation plans prepared by Natural England — and the Nature Restoration Fund, into which developers pay a Nature Restoration Levy to discharge certain environmental obligations. When an EDP is in place, a developer can choose to pay the levy and have the Habitats Regulations, Wildlife and Countryside Act, and Protection of Badgers Act obligations (for the features covered) treated as discharged. Natural England is then responsible for delivering the conservation measures at catchment scale. Commencement orders were laid on 19 December 2025; the first nutrient neutrality EDPs are expected to go to consultation in spring or summer 2026.

The significance for capital markets cuts both ways. For developers, the NRF promises faster consenting and cost certainty. For private nature markets, it introduces a genuine competing supply of state-delivered mitigation at potentially below-market prices. The Environmental Audit Committee has already flagged that the NRF may create uncertainty for private nutrient credit suppliers; the Chartered Institute of Ecology and Environmental Management has gone further, with some legal commentators describing the regime as a "licence to kill nature." Whether private nature markets can coexist with — or are displaced by — a state-operated levy fund is the defining structural question of 2026.

3. The Voluntary Markets: Codes, Registries, and the Integrity Problem

Outside the compliance regime, UK voluntary nature markets have grown around three core standards. The Woodland Carbon Code (WCC), operating since 2011, is the UK's quality assurance standard for woodland creation projects; by the end of 2023 it had over 2,000 registered projects. The Peatland Code, governing peatland restoration, has grown at an average annual rate of roughly 190% since 2017, with the majority of projects in Scotland. Both issue carbon units tracked on the UK Land Carbon Registry. The Wilder Carbon Standard, launched by The Wildlife Trusts, goes further — assuring both carbon sequestration and biodiversity recovery, and matching supply only to buyers who are demonstrably reducing their own emissions.

The economics of these markets are modest but instructive. Pending Issuance Units (PIUs) under the Peatland Code have typically traded between £15 and £25, while verified Peatland Carbon Units (PCUs) are issued only after five years of monitored restoration. Woodland carbon credits trade at higher prices, reflecting more mature verification pathways and longer sequestration durations. Both codes now explicitly engage with bundling — the inclusion of unquantified biodiversity and water benefits within a carbon unit — and are developing methods for stacking, where separate credits for carbon, biodiversity, and water can be issued from the same project.

Stacking creates a live integrity problem. If a hectare of restored peatland generates a carbon credit, a biodiversity credit, and a nutrient mitigation credit, the risk is double- or triple-counting the same environmental outcome. The government's position, articulated in the 2023 Nature Markets Framework and its ongoing responses to the 2024 Voluntary Carbon and Nature Markets consultation, is cautiously supportive of stacking provided quantification is robust. This is exactly the gap that the BSI Nature Investment Standards are designed to fill. Flex 701 sets overarching principles; Flex 702 addresses biodiversity markets specifically; Flex 704 covers nutrient markets; and the forthcoming Flex 705 Communities Code of Practice deals with benefit-sharing with local stakeholders. A full government response to the consultation is expected in summer 2026.

4. The Disclosure Stack: TNFD, ISSB, and the Path to Mandatory Nature Reporting

If BNG and nutrient neutrality are the supply-side mechanisms, nature-related disclosure is the demand-side mechanism — the information infrastructure that lets investors price nature risk across portfolios. The Taskforce on Nature-related Financial Disclosures (TNFD), whose secretariat is hosted by the Green Finance Institute (GFI) in London, published its final recommendations in September 2023. They are structured around the same four pillars as the climate disclosure regime covered in Day 4 of this course — governance, strategy, risk and impact management, and metrics and targets — and are designed to be fully interoperable with the UK SRS.

As of early 2026, more than 730 organisations globally have committed to adopt the TNFD framework, representing approximately $22.4 trillion in assets under management. Ninety-five of those are UK companies. The GFI also convenes the TNFD UK Consultation Group, with over 1,300 members and 600 companies. Research cited by the GFI indicates that 57% of UK asset owners already invest in natural capital, with a further 41% of non-investors planning first allocations within five years.

The regulatory trajectory is now clearer. In November 2025, the International Sustainability Standards Board (ISSB) announced it would begin standard-setting on nature-related risks, drawing directly on the TNFD recommendations. The ISSB is targeting an exposure draft by October 2026. Because the UK government has committed to assessing any new ISSB standards for use within the UK SRS framework, a future mandatory UK nature disclosure regime — parallel to the climate regime being finalised under FCA CP26/5 — is now a plausible 2028–2030 outcome rather than a distant possibility. For institutional investors building nature-related risk models, the runway is short.

The Designer's Corner (3 mins)

Design Challenge: Making Ecosystem Services Legible to Capital

Natural capital presents a design problem that carbon largely does not: heterogeneity. One tonne of CO₂ is fungible with any other tonne of CO₂, which is why carbon markets could standardise relatively quickly. A hectare of restored chalk stream in Hampshire is not fungible with a hectare of blanket bog in the Flow Country — the species, the hydrology, the carbon sequestration profile, and the local community interests are all different. For product designers working on natural capital platforms, the core challenge is: how do you build interfaces that preserve ecological specificity while still enabling portfolio-level decisions?

Problem 1: Unit heterogeneity and false comparability. A developer buying biodiversity units, a corporate buyer sourcing Woodland Carbon Code credits, and a pension fund allocating to a natural capital strategy are all looking at different things, measured by different metrics, verified by different bodies. A naive interface might present these as interchangeable tiles in a marketplace — creating exactly the kind of apparent-fungibility that undermined the legacy voluntary carbon market covered in Day 7. Design implication: Build explicit provenance panels into any unit-level view — showing habitat type, catchment, verification body, monitoring regime, and duration commitment. Resist the temptation to roll these into a single "quality score"; surface the dimensions separately so that buyers make comparisons on the axes that matter for their specific obligation.

Problem 2: The compliance–voluntary boundary. After the Planning and Infrastructure Act, a single land parcel might generate statutory BNG units, private nutrient credits, voluntary Peatland Code credits, and receive public Sustainable Farming Incentive payments — all potentially subject to double-counting restrictions and stacking rules that are still being written. A platform that treats these as independent line items will give users a misleading view of what can actually be sold, to whom, and when. Design implication: Treat stacking logic as a first-class primitive in the data model. Every credit should carry metadata about which other credits it can coexist with on the same parcel, what the double-counting rules are, and whether any public funding creates additionality exclusions. This extends the institutional literacy principle established on Day 1: users need the rules surfaced inside the product, not hidden in a 60-page Defra guidance document.

Problem 3: The state-vs-market visibility problem. The emergence of the Nature Restoration Fund creates a structural risk for investors in private nature markets — state-delivered mitigation at levy-set prices may undercut private credit suppliers in specific catchments. But this information is not currently consolidated anywhere. Which EDPs are in force? What levy rates has Natural England proposed? Where does private supply still command a premium, and where is it being commoditised? Design implication: Build a state-exposure layer into natural capital investment dashboards — a spatial view that overlays active and draft EDPs onto the landowner's or investor's portfolio, with flags for catchments where a private position is likely to face NRF price pressure. This is the nature-markets equivalent of the merchant tail risk visualisation challenge raised in Day 3's Designer's Corner: a structural revenue risk that only becomes visible when you model the institutional context, not just the asset.

Key Terms

Term	Definition
Natural Capital	The stock of renewable and non-renewable natural resources — soils, water, biodiversity, minerals — that combine to yield a flow of benefits (ecosystem services) to people and the economy. Treated in UK policy as an asset class analogous to financial capital.
Ecosystem Services	The flows of value that natural capital stocks generate, including provisioning services (food, timber), regulating services (flood attenuation, pollination, carbon sequestration), and cultural services (recreation, wellbeing).
Biodiversity Net Gain (BNG)	The statutory requirement in England for most new developments to deliver at least a 10% measurable improvement in biodiversity value, secured for at least 30 years, under the Environment Act 2021.
Nutrient Neutrality	A planning requirement in 74 English local authorities where new developments must not increase nitrogen or phosphorus loads to protected water bodies already in unfavourable condition.
Environmental Delivery Plan (EDP)	A spatially defined conservation plan prepared by Natural England under the Planning and Infrastructure Act 2025, enabling developers to discharge specified environmental obligations by paying a levy into the Nature Restoration Fund.
Stacking and Bundling	Stacking refers to selling separate credits (e.g. carbon, biodiversity, water) from the same piece of land to different buyers. Bundling refers to selling a single unit that incorporates multiple benefits. Both raise integrity risks around additionality and double-counting.
TNFD	The Taskforce on Nature-related Financial Disclosures — the global framework for corporate and financial institution disclosure of nature-related dependencies, impacts, risks and opportunities (DIROs), hosted by the Green Finance Institute.

Sources

Defra — Unlocking England's Nature Markets (24 March 2026): Announcement of the BSI Flex 702 (Biodiversity markets) and Flex 704 (Nutrient markets) standards and consultation on Flex 705 (Communities Code of Practice), valuing the UK natural environment at £1.5 trillion. defraenvironment.blog.gov.uk
GOV.UK — Implementing the Nature Restoration Fund (December 2025): The government's implementation plan for the Nature Restoration Fund and Environmental Delivery Plans, published alongside the Planning and Infrastructure Act 2025 receiving Royal Assent on 18 December 2025. gov.uk — NRF implementation plan
POST Parliament — Changes to Nutrient Neutrality in England (April 2026): Parliamentary Office of Science and Technology briefing on the shift from the existing nutrient neutrality regime to EDP-based mitigation, including the Environmental Audit Committee's concerns about implications for private nature markets. post.parliament.uk
HM Treasury — Enabling a Natural Capital Approach (ENCA) Guidance (February 2026): The updated supplementary guidance to the Green Book, with expanded material on valuing biodiversity and generating income streams from natural capital. gov.uk — ENCA guidance
Green Finance Institute — TNFD UK Consultation Group and Nature Data and Metrics Hub (April 2026): GFI's hub of resources for UK businesses piloting and adopting the TNFD framework, including the 2026 GFI Nature Transition Plan Pilot Group. greenfinanceinstitute.com
GOV.UK — Understanding Biodiversity Net Gain (updated 2025–26): The definitive guidance page covering the 10% BNG requirement, the biodiversity metric, the biodiversity gain hierarchy, and the May 2026 extension to Nationally Significant Infrastructure Projects. gov.uk — BNG guidance
POST Parliament — Biodiversity Net Gain (2025): Parliamentary briefing summarising the BNG regime, the 2024 National Audit Office findings, and ongoing concerns about ecological skills capacity and monitoring. post.parliament.uk
A&O Shearman — UK Biodiversity Net Gain: The Requirements, The Context, and What Businesses Need to Know (March 2026): Legal and market analysis of BNG as a compliance regime, including its interaction with the Kunming-Montreal Global Biodiversity Framework and TNFD. aoshearman.com